yes
yes
Depends on what you want to build. also depends on what you mean by advanced java. but really no, your knowledge becomes "advanced" as a result of practice, finding problems and then solving them. theres no way to learn advanced concepts without building simple things.
yup.
https://dreambot.org/guides/scripter-guide/script-dev/setting-up-dev-env/ dreambot guides on how to get ur first script going
https://dreambot.org/javadocs/allclasses-noframe.html this is a searchable list of all classes and methods you will need to write scripts.
https://discord.gg/wvZaH3W this is the dreambot edu discord server, here you can ask questions on how to do stuff and get answers quickly
https://github.com/milasoft/looter/blob/master/src/milasoft/looter this is my favourite example script. its old so you dont want to copy the actual methods in it. e.g. getBank().open is using the old dreambot api, now it would be Bank.open(), but the overall way the script is designed gives you a good idea on how to do some more complex things